JP2023134084A - Electronic circuit, module and system - Google Patents

Abstract

To avoid accidentally cutting off a power source and an electronic circuit when a small device is used.SOLUTION: An electronic circuit comprises a load, a load switch for switching the connection state between the power source and the load to either a conductive state or a non-conductive state, a first power conversion circuit for outputting a first DC power on the basis of a first power obtained by a first radio wave received by a first antenna, a second power conversion circuit for outputting a second DC power on the basis of a second power obtained by a second radio wave received by a second antenna, and a control circuit having a first input terminal, a second input terminal, and an output terminal that makes the load switch conductive when the first DC power is input to the first input terminal and that makes the load switch non-conductive when the second DC power is input to the second input terminal. The load switch is controlled to maintain the conductive state even if the second antenna receives the second radio wave in the conductive state.SELECTED DRAWING: Figure 1

Description

The present invention relates to electronic circuits, modules and systems.

In modern times, small devices in which a power source such as a battery is mounted on a substrate are used in various fields. Examples of such small devices include a medical device used inside the human body and an electronic key disclosed in Patent Document 1. For these small devices, it is desirable to reduce standby power as much as possible and extend the life of the power supply, taking into account the period during which they are stored in inventory, the period when they are not in operation, etc.

JP2011-024332A

An example of a technique for extending the life of a power supply is a technique in which the power supply and the electronic circuit are cut off, and then a switch is used to connect the power supply and the electronic circuit when the small device starts to be used. However, since the above-described switch has a mechanical mechanism, it may not operate properly. In addition, if the above-mentioned switch requires a waterproof structure such as resin sealing for a small device, a member that works with the switch and protrudes outside the waterproof structure is required, which reduces the waterproof performance of the waterproof structure. Sometimes I let it happen.

Alternatively, an example of a technology that extends the lifespan of a power supply is a technology that wirelessly transmits power to a small device, such as the electronic key mentioned above, and uses that power to connect the power supply and an electronic circuit. It will be done. However, this technique may not be able to disconnect the power source and the electronic circuit again after connecting the power source and the electronic circuit. Furthermore, if a small device adopts technology that can cut off the power supply and electronic circuit again after connecting the power source and the electronic circuit, the small device may receive unintended radio waves and the small device may be used. Nevertheless, the power supply and electronic circuits may be cut off.

The present invention has been made in view of the above-mentioned problems, and provides an electronic circuit, a module, and The purpose is to provide a system.

In order to achieve the above object, an electronic circuit according to one aspect of the present invention includes a load driven by electric power supplied from a power source, and an electronic circuit connected between the power source and the load, and an electronic circuit connected between the power source and the load. a load switch that switches a connection state to either a conductive state in which power is supplied from the power source to the load or a non-conductive state in which power is cut off from the power source to the load; and a first antenna. a first power conversion circuit that outputs first DC power based on first power obtained from a first radio wave received by the antenna; a second power conversion circuit that outputs two DC power, a first input terminal connected to the first power conversion circuit, a second input terminal connected to the second power conversion circuit, and the first DC power. is input to the first input terminal, the load switch is rendered conductive, and when the second DC power is input to the second input terminal, the load switch is rendered non-conductive; and a control circuit having a control circuit, wherein the load switch is controlled to maintain the conductive state even if the second radio wave is received by the second antenna while the load switch is in the conductive state. be done.

Further, in the electronic circuit according to one aspect of the present invention, the load switch may block a path from the second antenna to the second input terminal based on the output from the output terminal or the output from the load. By doing so, it is controlled to maintain the conductive state.

Further, in the electronic circuit according to one aspect of the present invention, the load switch is configured such that a cutoff switch provided in the path makes the path non-conductive based on the output from the output terminal or the output from the load. By setting it in the state, it is controlled to maintain the conductive state.

Further, in the electronic circuit according to one aspect of the present invention, the cutoff switch constitutes a matching circuit provided in the path.

Further, in the electronic circuit according to one aspect of the present invention, the load switch may introduce an output from the output terminal or an output from the load to a resistor connected to a matching circuit provided in the path. The matching constant of the matching circuit is changed to maintain the conductive state.

Further, in the electronic circuit according to one aspect of the present invention, at least two of the load switches are provided, and the control circuit is driven by DC power supplied from the power source, and the control circuit is driven by DC power supplied from the power source, and First, even if a path from the power source to the control circuit is cut off based on the output from the load, the load switch is controlled to maintain a conductive state.

Further, in the electronic circuit according to one aspect of the present invention, at least two of the load switches are provided, and the control circuit is driven by DC power supplied from the power source, and the control circuit is driven by DC power supplied from the power source, and First, even if a path from the control circuit to the load switch is cut off based on the output from the load, the load switch is controlled to maintain a conductive state.

Further, in the electronic circuit according to one aspect of the present invention, the control circuit is a flip-flop or an ultra-low current consumption weak signal detector.

In order to achieve the above object, a module according to one aspect of the present invention includes any one of the electronic circuits described above and a power source that outputs DC power.

Further, in the module according to one aspect of the present invention, the electronic circuit and the power source are housed in a waterproof casing.

In order to achieve the above object, a system according to one aspect of the present invention includes any one of the modules described above and a transmitter that transmits predetermined radio waves to the module.

According to the present invention, it is possible to provide an electronic circuit, a module, and a system that can prevent a power source and an electronic circuit from being accidentally cut off when a small device is in use.

FIG. 1 is a diagram showing an example of an electronic circuit according to a first embodiment. It is a figure showing an example of an electronic circuit concerning a modification of a 1st embodiment. FIG. 7 is a diagram showing an example of an electronic circuit according to a second embodiment. It is a figure showing an example of an electronic circuit concerning a modification of a 2nd embodiment. It is a figure showing an example of an electronic circuit concerning a 3rd embodiment. It is a figure showing an example of an electronic circuit concerning a modification of a 3rd embodiment. It is a figure showing an example of an electronic circuit concerning a 4th embodiment. It is a figure showing an example of the electronic circuit concerning a 5th embodiment. It is a figure showing an example of an electronic circuit concerning a 6th embodiment. It is a figure showing an example of an electronic circuit concerning a modification of a 6th embodiment. It is a figure showing an example of an electronic circuit concerning a 7th embodiment. FIG. 1 is a diagram illustrating an example of a system including an electronic circuit according to a first embodiment.

[First embodiment]
An electronic circuit according to a first embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an example of an electronic circuit according to the first embodiment. As shown in FIG. 1, the electronic circuit 1a includes a first antenna 11a, a matching circuit 12a, an RF (Radio Frequency)-DC (Direct Current) conversion circuit 13a, a booster circuit 14a, and a second antenna 21a. It includes a matching circuit 22a, an RF-DC conversion circuit 23a, a booster circuit 24a, a cutoff switch 25a, a control circuit 30a, a load 40a, a load switch 41a, and a power source 50a.

The first antenna 11a receives a first radio wave that is a starting point for turning on the load switch 41a, and converts the first radio wave into first power. The matching circuit 12a, the RF-DC conversion circuit 13a, and the booster circuit 14a constitute a first power conversion circuit that outputs first DC power based on the first power. The matching circuit 12a realizes impedance matching between the first antenna 11a and the RF-DC conversion circuit 13a. The RF-DC conversion circuit 13a converts the AC power output from the matching circuit 12a into DC power. The boost circuit 14a boosts the DC power output from the RF-DC conversion circuit 13a to a desired voltage to generate and output first DC power.

The second antenna 21a receives a second radio wave that serves as a starting point for turning the load switch 41a into a non-conductive state, and converts the second radio wave into second power. The matching circuit 22a, the RF-DC conversion circuit 23a, and the booster circuit 24a constitute a second power conversion circuit that outputs second DC power based on the second power. The matching circuit 22a realizes impedance matching between the second antenna 21a and the RF-DC conversion circuit 23a. The RF-DC conversion circuit 23a converts the AC power output from the matching circuit 22a into DC power. The booster circuit 24a boosts the DC power output from the RF-DC conversion circuit 23a to a desired voltage to generate and output second DC power. The cutoff switch 25a is a switch provided in a path from the booster circuit 24a to the control circuit 30a, and is switched from a conductive state to a non-conductive state based on the output from the control circuit 30a.

Further, it is preferable that measures are taken to prevent the first antenna 11a and the second antenna 21a from interfering with each other. For example, it is preferable that one of the first antenna 11a and the second antenna 21a is an electric field detection type antenna, and the other is a magnetic field detection type antenna. Alternatively, it is preferable that the first antenna 11a and the second antenna 21a are installed at different positions. Alternatively, it is preferable that the installed positions of the first antenna 11a and the second antenna 21a are shifted from each other by 90 degrees. Alternatively, it is preferable that the first antenna 11a and the second antenna 21a have different frequency directivities.

The control circuit 30a is, for example, a JK flip-flop. The control circuit 30a operates using power supplied from the power supply 50a. The control circuit 30a includes a first input terminal, a second input terminal, and an output terminal. The first input terminal is connected to the booster circuit 14a, and receives the first DC power. The second input terminal is connected to the booster circuit 24a and receives the second DC power. The output terminal brings the load switch 41a into a conductive state when the first DC power is input to the first input terminal. The output terminal brings the load switch 41a into a non-conductive state when the second DC power is input to the second input terminal.

In addition, the output terminal is configured such that the first DC power input to the first input terminal is extremely weak and is less than a predetermined first threshold value, and the second DC power input to the second input terminal is extremely weak. If the current state of the load switch 41a is less than the second predetermined threshold value, the current state of the load switch 41a is maintained. On the other hand, in the output terminal, a first DC power equal to or higher than a predetermined first threshold is input to the first input terminal, a second DC power equal to or higher than the predetermined second threshold is input to the second input terminal, and the load switch 41a When the load switch 41a is in a conductive state, the load switch 41a is brought into a non-conductive state. Further, the output terminal is such that a first DC power equal to or higher than a predetermined first threshold is input to the first input terminal, a second DC power equal to or higher than the predetermined second threshold is input to the second input terminal, and the load switch 41a When the load switch 41a is in a non-conductive state, the load switch 41a is made in a conductive state. In addition, cases where the first DC power equal to or higher than a predetermined first threshold is input to the first input terminal and the second DC power equal to or higher than the predetermined second threshold is input to the second input terminal are as follows. can be mentioned. For example, in such a case, the radio waves, which can be considered as plane waves, are transmitted by the first antenna 11a and the second antenna 21a because they are transmitted from a place sufficiently far away from the first antenna 11a and the second antenna 21a. An example is a case where the first DC power is received and the first DC power is equal to or higher than a predetermined first threshold value, and the second DC power is equal to or higher than a predetermined second threshold value.

The load 40a is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1a is mounted. The load 40a operates by receiving power from the power source 50a when the load switch 41a is in a conductive state. On the other hand, when the load switch 41a is in a non-conductive state, the load 40a does not receive power from the power source 50a, and therefore does not operate. The power source 50a is, for example, a battery.

The load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Specifically, in the load switch 41a, the cutoff switch 25a provided in the path from the second antenna 21a to the second input terminal is brought into a non-conducting state based on the output from the output terminal. It is controlled so that the conductive state is maintained. Once the cutoff switch 25a is rendered non-conductive based on the output from the output terminal, it cannot be rendered conductive again based on the output from the output terminal.

The electronic circuit 1a according to the first embodiment has been described above. The electronic circuit 1a is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, even if the second radio wave is received by the second antenna 21a while the load 40a is in use, the electronic circuit 1a prevents the load 40a from being erroneously cut off from being supplied with power from the power source 50a. be able to.

[Modification of the first embodiment]
An electronic circuit according to a modification of the first embodiment will be described with reference to FIG. 2. In the description of the modification of the first embodiment, the same components as in the above-described embodiment are given the same reference numerals, and descriptions regarding content that overlaps with the above-described embodiment are omitted as appropriate. FIG. 2 is a diagram showing an example of an electronic circuit according to a modification of the first embodiment. As shown in FIG. 2, the electronic circuit 1b includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22a, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a cutoff switch 25a, a control circuit 30b, a load 40b, a load switch 41a, and a power source 50a.

The control circuit 30b is, for example, a JK flip-flop. The control circuit 30b operates using power supplied from the power supply 50a. The control circuit 30b includes a first input terminal, a second input terminal, and an output terminal. The first input terminal is connected to the booster circuit 14a, and receives the first DC power. The second input terminal is connected to the booster circuit 24a and receives the second DC power. The output terminal brings the load switch 41a into a conductive state when the first DC power is input to the first input terminal. The output terminal brings the load switch 41a into a non-conductive state when the second DC power is input to the second input terminal.

In addition, the output terminal is configured such that the first DC power input to the first input terminal is extremely weak and is less than a predetermined first threshold value, and the second DC power input to the second input terminal is extremely weak. If the current state of the load switch 41a is less than the second predetermined threshold value, the current state of the load switch 41a is maintained. On the other hand, in the output terminal, a first DC power equal to or higher than a predetermined first threshold is input to the first input terminal, a second DC power equal to or higher than the predetermined second threshold is input to the second input terminal, and the load switch 41a When the load switch 41a is in a conductive state, the load switch 41a is brought into a non-conductive state. Further, the output terminal is such that a first DC power equal to or higher than a predetermined first threshold is input to the first input terminal, a second DC power equal to or higher than the predetermined second threshold is input to the second input terminal, and the load switch 41a When the load switch 41a is in a non-conductive state, the load switch 41a is made in a conductive state.

The load 40b is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1b is mounted. The load 40b operates by receiving power from the power source 50a when the load switch 41a is in a conductive state. On the other hand, when the load switch 41b is in a non-conductive state, the load 40b does not receive power from the power source 50a, and therefore does not operate. The load 40b makes the cutoff switch 25a non-conductive when the load switch 41a becomes conductive and starts operation or after the load switch 41a becomes conductive. Thereby, the load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Further, once the cutoff switch 25a is brought into a non-conductive state based on the output from the load 40b, it can be brought into a conductive state again based on the output from the load 40b.

The electronic circuit 1b according to the modification of the first embodiment has been described above. The electronic circuit 1b is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, even if the second radio wave is received by the second antenna 21a while the load 40b is in use, the electronic circuit 1b prevents the load 40b from being erroneously cut off from being supplied with power from the power source 50a. be able to. Further, the electronic circuit 1b can once turn the cutoff switch 25a into a non-conductive state and then turn the cutoff switch 25a into a conductive state again based on the output from the load 40b.

[Second embodiment]
An electronic circuit according to a second embodiment will be described with reference to FIG. 3. In the description of the second embodiment, the same reference numerals are given to the same components as in the above-described embodiment or modified example, and explanations regarding content that overlaps with the above-described embodiment or modified example are omitted as appropriate. FIG. 3 is a diagram showing an example of an electronic circuit according to the second embodiment. As shown in FIG. 3, the electronic circuit 1c includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22c, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a control circuit 30c, a load 40a, a load switch 41a, and a power source 50a.

The matching circuit 22c, the RF-DC conversion circuit 23a, and the booster circuit 24a constitute a second power conversion circuit that outputs second DC power based on the second power. The matching circuit 22c includes a matching element 221c and a cutoff switch 222c. The matching element 221c and the cutoff switch 222c realize impedance matching between the second antenna 21a and the RF-DC conversion circuit 23a. The cutoff switch 222c is, for example, a field effect transistor (FET). Further, the cutoff switch 222c is switched from a conductive state to a non-conductive state based on the output from the control circuit 30c.

The control circuit 30c is, for example, a JK flip-flop. The control circuit 30c operates using power supplied from the power supply 50a. The control circuit 30c includes a first input terminal, a second input terminal, and an output terminal.

The load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Specifically, in the load switch 41a, the cutoff switch 222c provided in the path from the second antenna 21a to the second input terminal is brought into a non-conductive state based on the output from the output terminal. It is controlled so that the conductive state is maintained. Once the cutoff switch 222c is rendered non-conductive based on the output from the output terminal, it cannot be rendered conductive again based on the output from the output terminal.

The electronic circuit 1c according to the second embodiment has been described above. The electronic circuit 1c is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, the electronic circuit 1c prevents the load 40a from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40a is in use. be able to. Furthermore, since the cutoff switch 222c is an element constituting the matching circuit 22c, the electronic circuit 1c does not need to be provided with the above-mentioned cutoff switch 25a, and can be realized with a smaller number of components. It has the advantage of

[Modification of second embodiment]
An electronic circuit according to a modification of the second embodiment will be described with reference to FIG. 4. In the description of the modification of the second embodiment, the same components as in the above-described embodiment or modification are given the same reference numerals, and descriptions regarding content that overlaps with the above-described embodiment or modification are omitted as appropriate. FIG. 4 is a diagram illustrating an example of an electronic circuit according to a modification of the second embodiment. As shown in FIG. 4, the electronic circuit 1d includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22c, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a control circuit 30b, a load 40d, a load switch 41a, and a power source 50a.

The load 40d is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1d is mounted. The load 40d operates by receiving power from the power source 50a when the load switch 41a is in a conductive state. On the other hand, when the load switch 41a is in a non-conductive state, the load 40d does not receive power from the power source 50a, and therefore does not operate. The load 40d makes the cutoff switch 222c non-conductive when the load switch 41a becomes conductive and starts operation or after the load switch 41a becomes conductive. Thereby, the load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Further, once the cutoff switch 222c is brought into a non-conductive state based on the output from the load 40d, it can be brought into a conductive state again based on the output from the load 40d.

The electronic circuit 1d according to the modification of the second embodiment has been described above. The electronic circuit 1d is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, the electronic circuit 1d prevents the load 40d from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40d is in use. be able to. Furthermore, since the cutoff switch 222c is an element constituting the matching circuit 22c, the electronic circuit 1d does not need to be provided with the above-mentioned cutoff switch 25a, and can be realized with a smaller number of parts. It has the advantage of Further, the electronic circuit 1d can make the disconnection switch 25a, which has been in a non-conductive state, conductive again based on the output of the load 40d.

[Third embodiment]
An electronic circuit according to a third embodiment will be described with reference to FIG. 5. In the description of the third embodiment, the same reference numerals are given to the same components as in the above-described embodiment or modified example, and explanations regarding content that overlaps with the above-described embodiment or modified example are omitted as appropriate. FIG. 5 is a diagram showing an example of an electronic circuit according to the third embodiment. As shown in FIG. 5, the electronic circuit 1e includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22e, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a resistor 25e, a control circuit 30e, a load 40a, a load switch 41a, and a power source 50a.

The matching circuit 22e, the RF-DC conversion circuit 23a, and the booster circuit 24a constitute a second power conversion circuit that outputs second DC power based on the second power. Matching circuit 22e includes a matching element 221e. The matching element 221e realizes impedance matching between the second antenna 21a and the RF-DC conversion circuit 23a. Furthermore, the matching element 221e is connected to a grounded resistor 25e. The matching constant of the matching circuit 22e changes depending on the potential difference between both ends of the resistor 25e.

The control circuit 30e is, for example, a JK flip-flop. The control circuit 30e operates using power supplied from the power supply 50a. The control circuit 30e includes a first input terminal, a second input terminal, and an output terminal.

The load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Specifically, in the load switch 41a, the output from the output terminal is introduced into the resistor 25e, a potential difference is generated, and the matching constant of the matching circuit 22e changes, making impedance matching impossible. The conduction state is maintained by preventing the RF-DC conversion circuit 23a from transmitting the 2 power.

The electronic circuit 1e according to the third embodiment has been described above. The electronic circuit 1e is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, even if the second radio wave is received by the second antenna 21a while the load 40a is in use, the electronic circuit 1e prevents the load 40a from being erroneously cut off from being supplied with power from the power source 50a. be able to.

[Modification of third embodiment]
An electronic circuit according to a modification of the third embodiment will be described with reference to FIG. 6. In the description of the modification of the third embodiment, the same components as in the above-described embodiment or modification are given the same reference numerals, and descriptions regarding content that overlaps with the above-described embodiment or modification are omitted as appropriate. FIG. 6 is a diagram showing an example of an electronic circuit according to a modification of the third embodiment. As shown in FIG. 6, the electronic circuit 1f includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22e, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a resistor 25e, a control circuit 30b, a load 40f, a load switch 41a, and a power source 50a.

The load 40f is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1f is mounted. The load 40f operates by receiving power from the power source 50a when the load switch 41a is in a conductive state. On the other hand, when the load switch 41a is in a non-conductive state, the load 40f does not receive power from the power source 50a, and therefore does not operate. The load 40f introduces its own output to the resistor 25e when or after the load switch 41a becomes conductive and starts operating. Thereby, the load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Further, even if the matching circuit 22e is once unable to realize impedance matching based on the output from the load 40f, it can again realize impedance matching by stopping the introduction of the output from the load 40f. .

The electronic circuit 1f according to the modification of the third embodiment has been described above. The electronic circuit 1f is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, the electronic circuit 1f prevents the load 40f from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40f is in use. be able to. Furthermore, even if the matching circuit 22e is unable to achieve impedance matching, the electronic circuit 1f can enable the matching circuit 22e to achieve impedance matching again based on the output of the load 40f.

[Fourth embodiment]
An electronic circuit according to a fourth embodiment will be described with reference to FIG. 7. In the description of the fourth embodiment, the same reference numerals are given to the same components as in the above-described embodiment or modified example, and explanations regarding content that overlaps with the above-described embodiment or modified example are omitted as appropriate. FIG. 7 is a diagram showing an example of an electronic circuit according to the fourth embodiment. As shown in FIG. 7, the electronic circuit 1g includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21g, a matching circuit 22g, and an RF-DC converter circuit 13a. It includes a conversion circuit 23g, a booster circuit 24g, a control circuit 30g, a load 40g, a load switch 41a, a load switch 42g, a control circuit switch 43a, and a power source 50a.

The control circuit 30g is, for example, a JK flip-flop. The control circuit 30g operates using power supplied from the power supply 50a. The control circuit 30g includes a first input terminal, a second input terminal, and an output terminal.

The load 40g is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1g is mounted. The load 40g makes the load switch 42g conductive after the load switch 41a is brought into conduction by the control circuit 30g. The load 40g operates by receiving power from the power source 50a via at least one of the load switch 41a and the load switch 42g. On the other hand, when the load switch 41a and the load switch 42g are in a non-conductive state, the load 40g does not receive power from the power source 50a, and therefore does not operate.

If the second radio wave is received by the second antenna 21g while the load switch 41a is in a conductive state, the load switch 41a becomes non-conductive, and the power supply to the load 40g may be cut off. In order to avoid this state, the load switch 42g is made conductive. Furthermore, even if the load switch 41a becomes non-conductive by making the control circuit switch 43g non-conductive and cutting off the power supply to the control circuit 30g in order to avoid the influence of the second radio wave, the load 40g Since the load switch 42g is in a conductive state, it is possible to continue the operation.

Further, the control circuit switch 43g can once make the path non-conductive based on the output from the load 40g, and then make it conductive again based on the output from the load 40g. In this case, the load switch 41a can again be controlled to be in a conductive state or a non-conductive state by the control circuit 30g, which operates by receiving power from the power supply 50a via the control circuit switch 43g.

The electronic circuit 1g according to the fourth embodiment has been described above. Even if the load switch 41a becomes non-conductive, the electronic circuit 1g makes the load switch 42g conductive and continues to operate the load 40g. Thereby, the electronic circuit 1g prevents the load 40g from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21g while the load 40g is in use. be able to.

[Fifth embodiment]
An electronic circuit according to a fifth embodiment will be described with reference to FIG. 8. In the description of the fifth embodiment, the same components as those in the above-described embodiment or modification are denoted by the same reference numerals, and descriptions regarding content that overlaps with the above-described embodiment or modification are omitted as appropriate. FIG. 8 is a diagram showing an example of an electronic circuit according to the fifth embodiment. As shown in FIG. 8, the electronic circuit 1h includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22a, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a control circuit 30g, a load 40h, a load switch 41a, a load switch 42g, a control switch 44h, and a power source 50a.

The load 40h is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1h is mounted. In the load 40h, after the load switch 41a is brought into conduction by the control circuit 30g, the load switch 42g is brought into conduction. The load 40h operates by receiving power from the power source 50a via at least one of the load switch 41a and the load switch 42g. On the other hand, when the load switch 41a and the load switch 42g are in a non-conductive state, the load 40h does not receive power from the power source 50a, and therefore does not operate.

If the second radio wave is received by the second antenna 21a while the load switch 41a is in a conductive state, the load switch 41a becomes non-conductive, and there is a possibility that the power supply to the load 40h may be cut off. In order to avoid this state, the load switch 42g is made conductive. Furthermore, even if the control switch 44h is made non-conductive to avoid the influence of the second radio wave and the load switch 41a is made non-conductive, the load 40h continues to operate because the load switch 42g is conductive. It becomes possible to do so.

Further, the control switch 44h once makes the path from the control circuit 30h to the load switch 41a non-conductive based on the output from the load 40h, and then makes the path conductive again based on the output from the load 40h. can be done. In this case, the load switch 41a can again be controlled to be in a conductive state or a non-conductive state by the control circuit 30g, which operates by receiving power from the power source 50a via the control switch 44h.

The electronic circuit 1h according to the fifth embodiment has been described above. Even if the load switch 41a becomes non-conductive, the electronic circuit 1h makes the load switch 42g conductive and continues to operate the load 40h. Thereby, the electronic circuit 1h prevents the load 40h from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40h is in use. be able to.

[Sixth embodiment]
An electronic circuit according to a sixth embodiment will be described with reference to FIG. 9. In the description of the sixth embodiment, the same components as those in the above-described embodiment or modified example are given the same reference numerals, and descriptions regarding content that overlaps with the above-described embodiment or modified example are omitted as appropriate. FIG. 9 is a diagram showing an example of an electronic circuit according to the sixth embodiment. As shown in FIG. 9, the electronic circuit 1i includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22a, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a cutoff switch 25a, a control circuit 30i, a resistor 35i, a load 40a, a load switch 41a, and a power source 50a.

The control circuit 30i is, for example, an ultra-low current consumption weak signal detector. The ultra-low current consumption weak signal detector requires power for operation at the nanoampere (nA) level, which is so small that there is no need to consider the life of the power source 50a. The control circuit 30i includes a first input terminal, a second input terminal, and an output terminal. The resistor 35i has the role of maintaining a conductive state by feeding back the signal output from the output terminal to the first input terminal.

The load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Specifically, in the load switch 41a, the cutoff switch 25a provided in the path from the second antenna 21a to the second input terminal is brought into a non-conducting state based on the output from the output terminal. It is controlled so that the conductive state is maintained. In addition, once the cutoff switch 25a makes the path non-conductive based on the output from the output terminal, it cannot make the path conductive again based on the output from the output terminal.

The electronic circuit 1i according to the sixth embodiment has been described above. The electronic circuit 1i is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, the electronic circuit 1i prevents the load 40a from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40a is in use. be able to. Moreover, since the control circuit 30i is an ultra-low current consumption weak signal detector, the electronic circuit 1i can achieve the effect with less power.

[Modification of the sixth embodiment]
An electronic circuit according to a modification of the sixth embodiment will be described with reference to FIG. 10. In the description of the modification of the sixth embodiment, the same components as in the embodiment or modification described above are denoted by the same reference numerals, and descriptions regarding content that overlaps with the embodiment or modification described above will be omitted as appropriate. FIG. 10 is a diagram illustrating an example of an electronic circuit according to a modification of the sixth embodiment. As shown in FIG. 10, the electronic circuit 1j includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22a, and an RF-DC converter circuit 13a. It includes a conversion circuit 23a, a booster circuit 24a, a cutoff switch 25a, a control circuit 30i, a resistor 35i, a load 40j, a load switch 41a, and a power source 50a.

The load 40j is a circuit mounted to realize the functions of a device such as a small device on which the electronic circuit 1j is mounted. The load 40j operates by receiving power from the power source 50a when the load switch 41a is in a conductive state. On the other hand, when the load switch 41a is in a non-conductive state, the load 40j does not receive power from the power source 50a, and therefore does not operate.

The load switch 41a is controlled to maintain the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. Specifically, in the load switch 41a, the cutoff switch 25a provided in the path from the second antenna 21a to the second input terminal is brought into a non-conducting state based on the output from the load 40j. It is controlled so that the conductive state is maintained. Further, once the cutoff switch 25a has made the path non-conductive based on the output from the load 40j, it can be made conductive again based on the output from the load 40j.

The electronic circuit 1j according to the modification of the sixth embodiment has been described above. The electronic circuit 1j is controlled so that the load switch 41a maintains the conductive state even if the second radio wave is received by the second antenna 21a while the load switch 41a is in the conductive state. . Thereby, the electronic circuit 1j prevents the load 40j from being erroneously cut off from being supplied with power from the power source 50a even if the second radio wave is received by the second antenna 21a while the load 40j is in use. be able to. Further, in the electronic circuit 1j, since the control circuit 30i is an ultra-low current consumption weak signal detector, the electronic circuit 1j can achieve the effect with less power.

[Seventh embodiment]
An electronic circuit according to a seventh embodiment will be described with reference to FIG. 11. FIG. 11 is a diagram showing an example of an electronic circuit according to the seventh embodiment. As shown in FIG. 11, the electronic circuit 1k includes a first antenna 11a, a matching circuit 12a, an RF-DC conversion circuit 13a, a booster circuit 14a, a second antenna 21a, a matching circuit 22a, and an RF-DC converter circuit 13a. This module includes a conversion circuit 23a, a booster circuit 24a, a cutoff switch 25a, a control circuit 30a, a load 40a, a load switch 41a, a power source 50a, and a waterproof structure 60k. The electronic circuit 1k is the same as the electronic circuit 1a according to the first embodiment except that it has a waterproof structure 60k. The waterproof structure 60k is, for example, a resin that covers the entire electronic circuit 1a without any gaps.

The electronic circuit 1k according to the seventh embodiment has been described above. Since the electronic circuit 1k includes the waterproof structure 60k, it can achieve the same effects as the electronic circuit 1a according to the first embodiment while avoiding problems caused by moisture intrusion.

In addition, in the above-mentioned embodiment or modified example, the case where the control circuit 30a, the control circuit 30b, the control circuit 30c, the control circuit 30e, and the control circuit 30g are JK flip-flops has been described as an example, but the present invention is not limited to this. . At least one of the control circuit 30a, control circuit 30b, control circuit 30c, control circuit 30e, and control circuit 30g may be another type of flip-flop, such as an RS flip-flop or an ultra-low current consumption weak signal detector. good.

Further, the electronic circuit according to the embodiment described above may be configured as a module including a power source that outputs DC power.

Furthermore, the electronic circuit according to the embodiment described above may be combined with a transmitter that transmits predetermined radio waves to configure a system. The predetermined radio waves referred to here are, for example, the above-mentioned first radio waves and second radio waves.

FIG. 12 is a diagram illustrating an example of a system including the electronic circuit according to the first embodiment. The system 100a includes an electronic circuit 1a and a transmitter 200a. The transmitter 200a is a mobile information processing terminal capable of wireless communication, such as a multifunctional mobile phone terminal (smartphone), a mobile phone terminal, a PDA (Personal Digital Assistant), a notebook PC, a tablet PC, or the like. Transmitter 70 is not limited to a mobile information processing terminal, and may be another information processing terminal. The transmitter 200a transmits the radio wave W to the electronic circuit 1a as a first radio wave or a second radio wave, for example. The radio waves W are radio waves emitted by a transmitting device during wireless communication performed according to a communication standard such as Bluetooth (registered trademark) or Wi-Fi (registered trademark). However, radio wave W is not limited to communication standards such as Bluetooth (registered trademark) and Wi-Fi (registered trademark), and can adopt various communication methods, and can be based on unique standards that do not apply to the default communication standards. It may be communication.

The embodiments of the present invention have been described above with reference to the drawings. However, the electronic circuit is not limited to the embodiments described above, and at least one of various modifications, substitutions, combinations, and design changes can be made without departing from the gist of the present invention.

Moreover, the effects of the embodiment of the present invention described above are the effects described as an example. Therefore, embodiments of the present invention may have other effects other than those described above that can be recognized by those skilled in the art from the description of the embodiments described above.

1a, ..., 1k...electronic circuit, 11a...first antenna, 12a...matching circuit, 13a...RF-DC conversion circuit, 14a...boosting circuit, 21a...second antenna, 22a, 22c, 22e...matching circuit, 221c, 221e... Matching element, 23a... RF-DC conversion circuit, 24a... Boost circuit, 25a, 222c... Cutoff switch, 25e... Resistor, 30a, 30b, 30c, 30e, 30g, 30i... Control circuit, 35i... Resistor , 40a, 40b, 40d, 40f, 40g, 40h, 40j...load, 41a, 42g...load switch, 43g...control circuit switch, 44h...control switch, 50a...power supply, 60k...waterproof structure, 100a...system , 200a...transmitter

Claims (11)

A load driven by power supplied from a power source;
Connected between the power source and the load, the connection state between the power source and the load is set to a conductive state where power is supplied from the power source to the load and a state where power is cut off from the power source to the load. a load switch that switches between a non-conducting state and a non-conducting state;
a first power conversion circuit that outputs first DC power based on first power obtained from a first radio wave received by a first antenna;
a second power conversion circuit that outputs second DC power based on second power obtained from a second radio wave received by a second antenna;
a first input terminal connected to the first power conversion circuit; a second input terminal connected to the second power conversion circuit; and when the first DC power is input to the first input terminal; a control circuit having an output terminal that brings the load switch into a conductive state and brings the load switch into a non-conductive state when the second DC power is input to the second input terminal;
Equipped with
The load switch is controlled to maintain the conductive state even if the second radio wave is received by the second antenna while the load switch is in the conductive state.
electronic circuit. The load switch is controlled to maintain a conductive state by cutting off a path from the second antenna to the second input terminal based on the output from the output terminal or the output from the load. Ru,
The electronic circuit according to claim 1. The load switch maintains a conductive state by making the path non-conductive based on the output from the output terminal or the output from the load by a cutoff switch provided in the path. controlled,
The electronic circuit according to claim 2. The cutoff switch constitutes a matching circuit provided in the path,
The electronic circuit according to claim 3. The load switch is configured such that the output from the output terminal or the output from the load is introduced into a resistor connected to a matching circuit provided in the path, and the matching constant of the matching circuit changes. , controlled to maintain conduction,
The electronic circuit according to claim 2. At least two load switches are provided,
The control circuit is driven by DC power supplied from the power source,
At least one of the load switches is controlled so that even if a path from the power source to the control circuit is cut off based on the output from the load, the load switch maintains a conductive state.
The electronic circuit according to claim 1. At least two load switches are provided,
The control circuit is driven by DC power supplied from the power source,
At least one of the load switches is controlled so that even if a path from the control circuit to the load switch is cut off based on an output from the load, the load switch is maintained in a conductive state. Ru,
The electronic circuit according to claim 1. The control circuit is a flip-flop or an ultra-low current consumption weak signal detector.
The electronic circuit according to any one of claims 1 to 7. The electronic circuit according to any one of claims 1 to 8,
A power supply that outputs DC power,
A module with. The electronic circuit and the power source are housed in a waterproof casing.
A module according to claim 9. The module according to claim 9 or 10,
a transmitter that transmits predetermined radio waves to the module;
A system equipped with

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